An o,o＇-methylene-bridged bisphenol A (BPA) dimer 2 was synthesized by a one-step reaction between formalin and excess BPA in the presence of a cation exchange resin in a polar aprotic solvent. Novel oligomeric polycyclic structures were synthesized by the reaction of reactive difunctional halides, methyl phosphonic dichloride, phenyl phosphonic dichloride, and dimethyl dichlorosilane with the BPA dimer under high-dilution conditions. The yields of the polycyclics were quite high. NMR and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) were very useful in the characterization of the dimer and its oligomeric polycyclic analogs. These polycyclics can potentially be used as precursors for advanced thermosetting materials. A series of polycarbonate copolymers of BPA were synthesized by solution polycondensation of the methylene bridged dimer of BPA with triphosgene. Alternatively, the co-polycarbonate containing crosslinkable moieties was synthesized by in-situ polymerization of BPA and BPA dimer with triphosgene. The copolymers were characterized by GPC. TG/DTA and DSC were used to investigate the thermal properties of the co-polycarbonates.